._header{
    background: white;
    z-index: 999;
  }
.public{
    width: 1200px;
    margin:0px auto;
}
.bg_header{
    height: 124px;
    border-top: 4px solid #ffcb00;
    overflow: hidden;
    .about{
        font-size: 12px;
        padding-top: 12px;
        box-sizing: border-box;
        height: 67px;
        margin-bottom: 15px;
        .logo{
            margin-left: 512px;
            margin-top: 20px;
        }
    }
    .nav{
        background: white;
        height:55px;
        margin-bottom: 1px;
        .firstli{
            float: left;
            line-height: 55px;
            font-size: 14px;
            margin-right: 38px;
            position: relative;
        }
        .search {
            width: 164px;
            height: 34px;
            background: #ffcb00;
            margin-top: 5px;
            input[type="text"] {
                width: 124px;
                height: 34px;
                border: none;
                outline: none;
                float: left;
                padding-left: 15px;
                box-sizing: border-box;
            }
            
            input[type="submit"] {
                width: 40px;
                height: 34px;
                border: none;
                outline: none;
                background-color: #ffcb00;
            }
        }

        
    }
}
.shadow{
    box-shadow:1px 2px 6px 0px gainsboro;
    z-index:999;
}
.menu_banner{
    height: 100px;
    display: none;
    background: white;
    position: absolute;
    top:30px;
}
.firstli:hover .menu_banner{
    display: block;
}